This invention relates to a method of manufacturing a semiconductor device and more particularly to a method of forming metal wiring for an integrated semiconductor circuit.
A method of forming metal wiring, for example, aluminium wiring for an integrated semiconductor circuit generally comprises the steps of forming an electrode contact hole in an insulating layer deposited on a semiconductor substrate by photoetching technique, thermally depositing an aluminium layer all over the insulating layer and patterning the aluminium layer by photoetching technique. However, the above-mentioned customary process of forming, for example, aluminium wiring had the drawbacks that since photoetching was carried out twice, high integration of a semiconductor circuit was obstructed; difficulties arose in projecting light for the patterning of an aluminium layer by photoetching; occurrence of etching residue of aluminium decreased the yield of a semiconductor device produced; and since little consideration was given to the shielding of an integrated semiconductor circuit manufactured by the prior art process, said circuit was readily affected by not only external but also internal noises.